diff --git a/pcdet/ops/ingroup_inds/ingroup_inds_op.py b/pcdet/ops/ingroup_inds/ingroup_inds_op.py
new file mode 100644
index 0000000..5c9b6e0
--- /dev/null
+++ b/pcdet/ops/ingroup_inds/ingroup_inds_op.py
@@ -0,0 +1,31 @@
+import torch
+
+try:
+    from . import ingroup_inds_cuda
+    # import ingroup_indices
+except ImportError:
+    ingroup_indices = None
+    print('Can not import ingroup indices')
+
+ingroup_indices = ingroup_inds_cuda
+
+from torch.autograd import Function
+class IngroupIndicesFunction(Function):
+
+    @staticmethod
+    def forward(ctx, group_inds):
+
+        out_inds = torch.zeros_like(group_inds) - 1
+
+        ingroup_indices.forward(group_inds, out_inds)
+
+        ctx.mark_non_differentiable(out_inds)
+
+        return out_inds
+
+    @staticmethod
+    def backward(ctx, g):
+
+        return None
+
+ingroup_inds = IngroupIndicesFunction.apply
\ No newline at end of file